Safety valve and drain for boilers



June 17, .1930.

T. J. KEENAN SAFETY-VALVE AND DRAIN FOR BOILERS Filed April 12, 1929 ZJZ'e/e n an ATTORNEY Patented June 17, 1930 UNITED STATES THOMAS J. KEENAN, OF STEUBEHVILLE, OHIO SAFETY VALVE AND I Application filed April 12,

My present invention has reference to a safety valve for house or like small hot water boilers, and the primary object is the provision of a device of this character which is screwed in the boiler and which includes a spring influenced valve that will automatically open by an over pressure of steam in the boiler, and thereby afford a safety device that will prevent the explosion of the 1e boiler.

A still further object is the provision of a device for this purpose in which the valve may be retained in open position, as when it is desired to drain the boiler.

To the attainment of theforegoingand other objects which will present themselves as the nature of the invention is better understood, the improvement also consists in certain other novel features of construction, 90 combination and operative association of parts, one satisfactory embodiment of which is disclosed by the accompanying drawings.

In the drawings:

Figure 1 is a side elevation of the inn provement in applied position, parts being in section. I

Figure 2 is a similar view of the improvement showing the valve moved and locked in unseated position as when'the boiler is to be drained.

Figure 3 is a detail sectional view through the'center portion of the body of the improvement.

As disclosed by Figure 1 of the drawings I screw in a boiler 1 the reduced and threaded end 2 of the valve body member 3 of the improvement.

The second or outer end of the body is preferably widened and is contacted by a washer which is let in a depression in a flanged cap 4 which is screwed on the said body. The body, at a suitable distance away from the open end that is closed by the cap 4 is inwardly directed and is formed with interior threads 5. In practice I have found that only two of these threads are required. Above the inwardly thickened or flanged threaded portion 5 the body is formed with a chamber 7 that communicates with a port or passage 8 that extends centrally through DRAIN FOR BOILERS 1929. Serial No. 354,647.

the threaded end of the body. The chamber 7 is in communication with a port or passage in a downwardly inclined extension 9 that is integrally. formed with the body. This pipe extension 9 preferably has its outer end widened, and the said end is threaded, as at 10, whereby a coupling for a hose may be attached to the body 3. I

The wall 11 between the chamber 9 and the passage 8 provides a seat for the. pref erably compressible face 12 of a valve member 13 which is preferably in the nature of a thickened disc. The lower portion of the valve is provided with threads 14 that are designed when the valve is unseated to engage with the threads 5 as disclosed by Figure 2 of the drawings'and thereby open the passage ,of the extension!) to the chamber 7 and likewise to the passage 8 in the body. The valve is provided with a stem 15 that passes through the packing ring 16 on the inner face of the flanged cap 4 and likewise passes centrally through the said cap.

The outer end of the stem 15'has attached thereto a handle 17. Surrounding the valve stem and received in the lower chamber of the body and exerting a pressure between the gasket 16 and one end of the valve 13 there is a coil spring 18. This spring is of suflicient strength to normally seat the valve 13 when the screw portion thereof does not engage with the interior screws 5 in the body. The spring 18, however, will yield when the valve is influenced by an overpressure of steam in'the boiler 1, so that the valve is thus opened and steam will escape through the passage 8, the chamber 7 and the passage in the extension 9 of the body. A downward pressure on the handle 17 will also unseat the valve and a turning of the handle will cause the threads 14 to engage with the interior threads 5 in the body so that the valve is held unseated as disclosed by Figure 2 of the drawings when the boiler is to be drained.

The simplicity and advantages of the construction will, it is thought, be perfectly apparent when the foregoing has been carefully read in connection with the accompanying drawings so that further description will not be required. However, I wish it understood that I do not desire being restricted to the precise details herein set forth and, therefore, hold myself entitled to make suchchanges therefrom as fairly fall within the scope of what I claim.

Having described the invention, I claim: A device for the purpose set forth comprising a valve body designed to have one end screwed in a boiler, said body having a central chamber therein, a second chamber outward of the central chamber, a flanged caprclosing the outer chamber, and interior threads between the chambers, said body also having an angle extension having a pas sage which communicates with the central chamber, a valve having a compressible facing received in the central chamber and de signed to close the passagebetween the central chamber and the end of the body connected with the boiler, said valve being round in cross section and having threads thereon, a stem extending from the valve and passing through the cap, a handle on the outer end of the stem, and a spring surrounding the stem, arranged in the bodyand exerting a pressure between the cap and the valve for" normally seating the valve, and said valve designed to be unseated when an outward pressure is exerted on the handle and the latter is turned to bring the threads of the valve into coengagement with the interior threads of the body.

In testimony whereof I aflix my signature.

THOMAS J. KEENAN. 

